Noncontrolling Interests (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Changes in the noncontrolling interests
Beginning Balance			$ 40,900,000	$ 46,600,000
Distributions to noncontrolling interests			(11,000,000)	(11,900,000)
Comprehensive income:
Net Income attributable to noncontrolling interests	2,200,000	1,200,000	5,700,000	6,200,000
Other comprehensive income, net of tax			0	0
Comprehensive income			5,700,000	6,200,000
Ending Balance	$ 35,600,000	$ 40,900,000	$ 35,600,000	$ 40,900,000